Evaporator unit



2 Sheets-Sheet 1 J. H. BENSON EVAPORAIOR UNIT Filed Feb. 2, 1953 winJune 8, 1937.

ATTORNE 6 I June 8, 1937. J. H. BENSON EVAPORATOR UNIT Filed Feb. 2,1953 2 Sheets-Sheet 2 i! i I '''A INVENTQR. L/OHN H. .BENSON 5m IMATTORNEYS Patented June 8, 1937 uulrso STATES EVAPORATOR UNIT.

John H. Benson, Salem, Ohio, assignor to Mullins ManufacturingCorporation, Salem, Ohio, a corporation of New York Application February2, 1933, Serial No. 654,899

Claims.

This invention relates to an evaporator unit, and has to do particularlywith a sheet metal cooling unit provided with a suitable header of thetype shown in Reissue Patent No. 18,182 of 6 September 8, 1931.

In sheet metal evaporators of this type, it is usually desirable to usea relatively small quantity of liquid refrigerant and hence to constructthe evaporator with a relatively small header.

10 It is also desirable to extend the side walls of the header radiallytherefrom so as to weld the side walls at a point very closely adjacentthe header. The reducing of the diameter of the header is usuallylimited because with a relatively small header a slight variation inlevel of the refrigerant would uncover the side passageways.

Other disadvantages in this type of sheet metal evaporator relate to theenameling wherein the subjecting of the header to a pressure frequentlycaused a slight movement of the metal at the point where the side wallsjoined the header with the result that the enamel often chipped orpeeled.

It is an object of the present invention to overcome any possibility ofoil logging due to a variation in level in the header and to make itpos-. sible to use a header of relatively small capacity. A furtherobject of the present invention is to strengthen the inner shell at thejuncture of the side walls and the header to prevent the porcelainenamel coating from chipping off the evaporator adjacent the header.This result is effected by using relatively short beads or bulletsdesigned to break up the flat areas and reinforce the header at thepoints of contact with the header halves, or otherwise at the pointwhere the entire structure is subjected to the greatest stress. 4

A still further object of the invention is to minimize disturbance ofboiling refrigerant entering the header from the side walls; bysubstantially doubling the area of the passageways as they enter theheader restriction is minimized and this results in much lessdisturbance. Other novel features of the invention will be more clearlyset forth in the specification and claims.

In the drawings:

Fig. 1 is a front elevation of a sheet metal evaporator embodying thepresent invention.

Fig. 2 is a sectional view taken on line 2-2 of Fig. 1, showing theincreased size of the passageways resulting from the beads or bullets.

Fig. 3 is a sectional view taken on line 33 of Fig. 2 and showing indetail the preferred location of the bullets.

Fig. 4 is a sectional view. taken on line 4-4 of Fig. 2 and showing onepair of bullets in elevation.

Fig. 5 is-a sectional view taken on line 5-5 of Fig. 3 showing themethod of fabricating the manifold for connecting the ends of the spacedI bullets.

Fig. 6 is a sectional view taken on line 6-6 of Fig. 3 showing themanifold in elevation and the bullets, in cross section.

Fig. '7 is a sectional view taken on line 1-1 of Fi 3.

The present invention is particularly applicable to evaporators of thetype wherein the side walls are formedintegral with the header walls,but it will be understood that my reinforcing bul lets are equallyadaptable to all evaporators having headers and side walls leadingtherefrom regardless of whether said side walls are weldedv to theheader or formed integrally therewith.

In the illustrated embodiment of the invention the evaporator is shownas consisting of a header 2 formed of two sections 3 and 4. Side walls 5and 8 are reinforced by means of suitable corrugations l and thesecorrugations act as passageways for distributing the liquid refrigerantfrom the header around the sharp freezing chamber. Longitudinalmanifolds 8 are formed longitudinally of the header and spaced therefromand bead members or bullets are fabricated as at 9 to extend from saidmanifolds inwardly A and radially to said header.

The evaporator may be of the type where the outer shell, including theportion 3 of the-header, and the corrugated side walls are fabricated inone piece with the side walls extending radially outwardly as shown atill in dotted lines in Fig. 1, and the inner shell and correspondingside walls formed to complementally fit with the outer shell so that theside walls may be welded together in between the corrugations and thenbent to the shape shown in Fig. 1.

Short beads or bullets ii are formed as a part of the inner shell and atthe point where the side walls 5 and 6 join the portion 4 of the header,

as best shown in Fig. 3. These bead members ll may be of any shape andmay join the header at any point in its circumference, but in thepreferred form the bullets are substantially semicircular, as best shownin Fig. 6 and are substantially the same shape as the corrugations 1formed in the outer shell of the evaporator. The. manifolds l2 areformed in the outer shell and extend parallel to the header and closelyadjacent thereto so that the side walls, as they leave 55 the header,are reinforced and they also make it possible to weld in between eachcorrugation and in between the manifold and the header as at the pointl3 so as to provide the greatest 5 amount of strength for the header atthe point subjected to the greatest stresses or, in other words, at thepoint most liable to rupture.

By using the bullets il in the particular embodiment shown in Fig. 3, itwill be seen that the level of the refrigerant may drop to the point l4before the oil will seal off the corrugations I from the header. Inother words, by using the bullets of the design shown in Figs. 3 and 4,I have provided the distance between the dotted lines I5 and H as anextra height to take care of refrigerant level variation in the headerto prevent oil from running down into the corrugations. This bulletstructure thus permits the header 2 to be made considerably smaller andthus requiring a less amount of refrigerant which is a condition towardwhich most refrigerator manufacturers are striving. After the weldingtogether of the two parts to form the top shell or header and thedownwardly extending shells the evaporator is usually enameled and thenafter enameling and before use it is subjected to a pressure test. Whilefrequently the pressure applied to the interior of the evaporator causesthe short portion which joins the header with the inner shell tostraighten out and flatten, the welding in between the corrugationsprevents any great straightening out but, nevertheless, a smallflattening occurs which has heretofore resulted in much chipping. By theadding of the short beads or bullets at this very important point of theevaporator I have stifiened the header where it meets the radial sidewalls and provided a structure which will resist the chipping or peelingaction heretofore caused by the straightening out of this angle. Thebullets also transmit some! of the stresses to the second row of spotson the other side of the manifold l2 away from he header.

As will be seen by comparing Figs. 6 and 7, the adding of the bullets orshort beads between the manifold and header in the inner shellsubstantially doubles the cross sectional area of the passagewaysentering the header, thus materially minimizing any disturbance due toboiling of the refrigerant entering the header from the passageways.

In the embodiment illustrated in Fig. 2 the entire evaporator is shownas being formed of two pieces with flanges l8 and I! at the front andback. This type of evaporator is particularly adaptable for use with ahigh side float or capillary tube and the inlet and outlet to and fromthe header may be located at any desired points in accordance withstandard practice.

What I claim is:

l. A sheet metal evaporator comprising outer and inner shells fabricatedto each form a portion of a header and laterally and downwardlydepending side walls, one of said laterally extending walls beingembossed to reinforce the same and provide passageways in communicationwith and extending into the header, and relatively short, beads formedin the other wall at the region where it connects into the headerwhereby to lower the possible level of the refrigerant in the evaporatorbefore uncovering the passageways of the side walls.

2. A sheet metal evaporator comprising outer and inner shells fabricatedto each form a por- 76 tion of a header and laterally and downwardlydepending side walls, one of said side walls being embossed to reinforcethe same and provide passageways leading from the header, and beadsformed in the other side wall and extending from the header a relativelyshort distance outwardly therefrom, some of said beads being inalignment with'the embossed portions of the outer shell entering theheader.

3. A sheet metal evaporator comprising outer and inner shells fabricatedto each form a portion of a header and radially and downwardly dependingside walls, the upper of said side walls being embossed to reinforce thesame and provide passageways extending from the header, and beads formedin the lower side walls and extending from the header a relatively shortdistance outwardly therefrom, some of said beads being in alignment withthe embossed portions I of the outer shell entering the header.

4. An enameled sheet metal evaporator comprising a header and outer andinner shells extending therefrom and directly connected thereto, theouter shell having embossed portions leading from points adjacent theheader and forming passageways, and the inner shell having a pluralityof relatively short embossed portions at the region where it joins theheader and positioned opposite to and in alignment with some of saidembossed portions whereby to reinforce the header to lower the eflectiverefrigerant level and prevent peeling off of the enamel when theevaporator is subjected to pressure.

5. An enameled sheet metal evaporator comprising outer and inner shellsfabricated to each form a portion of a header and laterally anddownwardly depending side walls, the outer side wall being embossed toprovide passageways extending from the header, a manifold formed in saidouter wall and extending transversely of the passageways at a pointadjacent the header, and short embossed beads formed in said inner walland extending from said manifold inwardly to the header, said beadslowering the eifective refrigerant level of the header and reinforcingthe. evaporator to prevent chipping of the enamel when the evaporator issubjected to pressure.

6. An enameled sheet metal evaporator comprising outer and inner shellsfabricatedto form a two piece evaporator, a header, and radially anddownwardly depending side walls, the outer side wall being embossed toprovide passageways extending from the header, a manifold formed in saidouter wall and extending transversely of the passageways at a pointadjacent the header,

and short embossed beads formed in said inner wall and extending fromsaid manifold inwardly to the header, said beads lowering the effectiverefrigerant level of the header and reinforcing the evaporator toprevent chipping of the enamel when the evaporator is subjected topressure.

7. A sheet metal evaporator comprising cute. and inner shells fabricatedto each form a portion of a header and laterally and depending sidewalls, the outer side wall being corrugated to form passagewaysextending from the header and the inner wall being generally flat, thewalls being welded together on lines between the corrugations, andrelatively short beads formed in the inner wall at the region where itjoins the header and registering with the corrugations whereby to lowerthe lowermost effective refrigerant level and to increase the area ofthe passageways immediately as they enter the header.

8. A sheet metal evaporator comprising a header, parallel inner andouter shells directly connected with said header for distributing liquidrefrigerant therefrom, said shells having angularly positioned portionsdefining at least two walls of a sharp freezing chamber, beads formed inone of said shells and extending from said header for substantially thecontinuous length of said two walls, and relatively short beads formedin said other shell and extending outwardly from the header and spacedlongitudinally of the header.

9. A sheet metal evaporator of the flooded type comprising an outer onepiece shell fabricated to form a centrally positioned arcuate depressionextending substantially but less than the width of the shell w andcorrugations extending laterally from each side of said arcuate portionand terminating short of the ends of the shell, an inner one piece shellfabricated to form a centrally positioned header portion adapted tocooperate with said arcuate portion on the outer shell to form a header,laterally extending walls cooperating with the corrugated walls of theouter shell, said cooperating walls of the inner and outer shell beingbent toform a sharp freezing chamber, said shells being fabricated toform matching flanges extending continuously around the completeperiphery of the shells, the shells being sealed together by asubstantially continuous weld extending around said flange, and

relatively short beads formed in the inner shell said walls beingcorrugated to form passageways leading from the header, said walls beingwelded together in the spaces between the corrugations, and relativelyshort beads formed in the other wall at the region where it enters theheader and cooperating with some of said passageways.

JOHN H. BENSON.

